Xu Jun, Zhang Gangsheng
College of Materials Science and Engineering, Guangxi University, Nanning, Guangxi 530004, China.
J Struct Biol. 2017 Mar;197(3):308-311. doi: 10.1016/j.jsb.2016.12.009. Epub 2016 Dec 23.
Nacre is one of the most attractive models for understanding the fundamental principles of biomineralization and for designing bio-inspired materials due to its simple structure but with unusual mechanical properties. It is made up of lamellae of aragonite tablets bonded together by the organic interlamellar membranes (ILMs), of which the latter occupy less than 5wt% of nacre. For a long time, previous authors failed to directly observe the crystallographic relationship between the ILM and aragonite tablet in bivalve shells. Here, using high resolution transmission electron microscope (HRTEM), we investigate the interfacial structure of the domed tablets that coexist with the flat ones in green mussels. We directly observed that the ILMs are oriented with the underlying tablets and connected with the latter via a superlattice region. The finding advances our current knowledge of nacre biomineralization and may help to design novel nacre-like materials.
珍珠层是理解生物矿化基本原理以及设计受生物启发材料的最具吸引力的模型之一，因为其结构简单却具有非凡的力学性能。它由文石片层通过层间有机膜（ILMs）粘结在一起组成，其中后者在珍珠层中所占比例不到5wt%。长期以来，先前的作者未能直接观察到双壳贝类贝壳中层间有机膜与文石片层之间的晶体学关系。在此，我们使用高分辨率透射电子显微镜（HRTEM）研究了绿贻贝中与扁平片层共存的圆顶片层的界面结构。我们直接观察到层间有机膜与下面的片层取向一致，并通过一个超晶格区域与后者相连。这一发现推进了我们目前对珍珠层生物矿化的认识，并可能有助于设计新型的类珍珠层材料。
